Leprosy

Leprosy (synonyms: Hansen’s disease, Hanseniasis, Hansenosis, Lepra) (from the Latin word lepra, which means “scaly” and the Greek lepo meaning “to scale”) is a chronic infective granulomatous disease caused by the bacillus Mycobacterium leprae, an intracytoplasmic parasite of Schwann cells and macrophages. It mainly affects the peripheral nervous system, skin, and other tissues such as the reticuloendothelial system, mucous membranes, the eyes, testes, bones and joints, muscles, and adrenal glands. Among communicable diseases, leprosy is one of the leading causes of permanent physical disability worldwide. The disease and resulting visible deformities contribute to the intense social stigma associated with this affliction, that provokes discrimination and avoidance of any contact with patients and their families. Pathogenic transmission occurs via person-to-person contact, especially through the nasorespiratory route, although there is some possibility of transplacental infection. Recently, zoonotic infections have also been reported. Once distributed worldwide, leprosy is now seen primarily in the tropical and subtropical regions of Asia, Africa, and Central and South America. This geographic distribution is likely due more to the poor living standards and hygiene than to the warmer climate. Although it can exceptionally be fatal, leprosy is still one of the most serious long term health problems in developing countries.